Dual energy CT: added value in gouty arthritis.

Gouty arthritis is an inflammatory reaction as a result of monosodium urate crystal deposition in synovial fluid and periarticular soft tissue. It is the most common form of inflammatory arthritis with an estimated prevalence of 5 per 1000 in the USA. Clinical diagnosis is difficult and definite diagnosis with positive urate crystal aspiration often is made late in the disease process. Dual energy computer tomography (DECT) is a relative new non-invasive imaging modality that is able to distinguish urate crystals from calcium in soft tissue and synovial fluid. In this case report we describe the potential of DECT in gout by clarifying the technical background and present two cases in which DECT confirms the clinical diagnosis and shows the extend of the disease. Although more extensive studies should be done to validate DECT in diagnosing gout, the preliminary results in diagnosing gout, determining the extensiveness and monitoring therapy are promising.